This invention relates to a freight container for transporting fluids.
German Offenlegungsschrift No. 2,828,349 discloses a freight container in which a tank for receiving the fluids is connected to an outer frame by bowl-shaped saddle pieces which have borders curved according to the tank profile and welded to a pair of tensioning rings surrounding the tank at locations near the two ends thereof. Saddle pieces of this type are excellently suited to guide the forces occurring on the tank immediately into the corners of the frame which, in accordance with the pertinent standards, are those portions at which forces can and must be transmitted to and from the exterior. The borders of the saddle pieces engaging the tank cause a good distribution of the forces via the tensioning rings over the tank periphery, thereby largely avoiding tension peaks.
In order to detach the tank from the frame in the known arangement, the tensioning rings which form the connection between the saddle pieces and the tank, each consists of two flange rings screwed together at their mutually facing flanges, one of the flange rings being welded to the tank shell and the other being welded to the saddle pieces.
Since any screw connection permits basically only a punctual transmission of force, the advantage of a uniform force distribution over the tank periphery would be lost to a certain degree if only two or few screws were employed in the known arrangement to obtain a detachable embodiment. If it is attempted to overcome this problem by a higher number of screws, the labor required in assembly and disassembly becomes considerable. In addition, screw connections disposed within the region of the saddle pieces are comparatively difficult to access. Finally, screw connections are often exposed to an increased danger of corrosion than for instance properly worked welds.
It is an object of the present invention to overcome the disadvantages occurring in prior art freight containers, more specifically to provide a freight container in which the tank and the frame are detachably interconnected. It is another object of this invention to achieve such detachable connection between the tank and the frame of a freight container by means which are as simple and inexpensive with respect to labor and material as possible, and in which an undisturbed transmission of forces between the tank and the frame corner regions is achieved.